1. Field of the Invention
The present invention related to a washing machine having a rinse mode for removing detergent from laundry therein.
2. Description of Related Art
Clothes washing machines generally include as part of their operation, a rinse mode to remove detergent from the laundry after a detergent washing. In a conventional washing machine operating in its rinse mode, so called hold water rinse mode, detergent wash water is discharged from the washing tub, after which the tub is filled by clean water. When the incoming new water reaches a predetermined level in the tub, the water supply is stopped and an agitator provided at the center of the tub is rotated. Detergent permeated into the laundry is dissolved into the new water in the tub by the action of the water being moved by the agitator. After a predetermined time, the water dissolving detergent is discharged from the tub. This process may be repeated one or more times. This hold water rinse mode operation wastes a considerable amount of water when the discharge and full filling is repeated.
Therefore, another type of rinse mode, a so called a spin dry rinse mode, which reduces the consumption of water, was developed. Spin dry rinse mode operation includes one or more spin dry rinse cycles. In each spin dry rinse cycle there is a spin dry rinse operation and a spin dry operation. In the spin dry rinse operation, water in the tub is drained from the tub after the detergent washing, then, new water is supplied into the tub while the tub is being rotated. The supplied water permeates into the laundry because of the tub rotation. After the spin dry rinse operation is completed, the spin dry operation is started. During spin dry operation, water supply is stopped, but rotation of tub continues. The permeating water is separated from the laundry and exhausted by the centrifugal force of the tub rotation. The spin dry rinse cycle including the stopping and starting water supply and tub rotation is repeated a predetermined number of times in spin dry rinse mode operation. This spin dry rinse mode can reduce the consumption of water. Further, the spin dry rinse mode is more efficient at removing detergent from laundry than the hold water rinse mode.
However, in the conventional washing machine, the spin dry rinse mode is carried out at a predetermined time period, and has a predetermined number of spin dry rinse cycles. Both the time period at which spin dry rinse mode operation takes place and the number of spin dry rinse cycles that will be carried out are preset and cannot be changed by user. The time period and the number of cycles are decided based on a heavy laundry load. In other words, the spin dry rinse mode is designed to handle loads in which much laundry is placed in the tub and much detergent is put into the tub such that the result of rinse mode is not insufficient. Therefore, when only a light load of laundry is being washed, the volume of water used in the spin dry rinse mode is often excessive, and the time period of the spin dry rinse mode is also significantly long for the laundry to be rinsed. Thus, the spin dry rinse mode operation, as now carried out is inefficient for light laundry loads. Furthermore, during spin dry rinse operation of the spin dry rinse mode, when the tub is rotating while water is being supplied to the tub, an unbalance of rotation often occurs.